Steam surface condenser



June 27, 19 7 L. L. FORSTER STEAM SURFACE CONDENSER 2 Sheets-Sheet 2Filed June 11, 1965 INVENTOR. LESLIE L. FORSTER AGENT United StatesPatent 3,327,774 STEAM SURFACE CONDENSER Leslie L. Forster, Easton, Pa.,assignor to Ingersoll-Rand Company, New York, N.Y., a corporation of NewJersey Filed June 11, 1965, Ser. No. 463,254 16 Claims. (Cl. 165-40)ABSTRACT OF THE DISCLOSURE Apparatus for use with a condenser forremoving noncondensable elements from condensate. It includes a chamberseparate from the condensate reservoir. Steam is introduced into theseparate chamber for increasing the pressure in the chamber to drive offnoncondensable elements and return them to the condenser inlet. There isapparatus for controlling the input of steam in response to conditionswhich indicate excess noncondensable elements.

This invention relates generally to steam surface, to condensers, andmore particularly to apparatus for removing noncondensable elements fromcondensate which results in a more efiicient condenser operation.

Heretofore, during periods of light load and/or low condensercirculating water temperature, a satisfactory degree of processing fordeaeration, degasification, and removal of other contaminates from thecondensate from a steam surface condenser is very diflicult to obtain.Attempts to achieve satisfactory processing under such stringentconditions heretofore have led to the heating of all of the condensatein the condenser hot Well by injecting external steam directly into thecondensate to raise the temperature of the condensate for removingtherefrom the noncondensable elements. The foregoing has not alwaysproven completely successful in producing a higher quality of cleansedcondensate because some of the noncondensables remain on or near thesurface of the condensate in the hot well and are not passed into thecooler for transmission to removal equipment. Thus, suchnoncondensa'bles are subject to reabsorption by the condensate in thehot well.

It is an object of the present invention to avoid and overcome theforegoing and other difiiculties of and objections to prior practices inassociation with steam surface condensers by positive venting or removalof noncondensable elements from steam when it is condensed to providecleansed condensate.

Another object of the present invention is to eliminate the reabsorptionof noncondensable elements by cooled portions of processed condensate.

Still another object of the present invention is to provide simple andefiicient deaerating processing apparatus for steam surface condensersfor removal of noncondensable elements from condensate in an atmospherenonconducive to reabsorption.

The present invention contemplates apparatus in association with acondenser having an inlet to receive steam, means for condensing suchsteam, means for removing noncondensables and for receiving condensateresulting from condensation; comprising chamber means for receivingcondensate from the condensate receiving means of the condenser andhaving a discharge line for condensate, means for freeing noncondensableelements from the condensate in the chamber means and for creatingpressure "ice in the chamber means in excess of pressure of the inletsteam flow of the condenser, and conduit means for passing freednoncondensables from the chamber means to the inlet steam flow of thecondenser.

The foregoing and other objects and advantages Will appear more fullyhereinafter from a consideration of the detailed description whichfollows, taken together with the accompanying drawings wherein severalembodiments of the invention are illustrated by way of example. It is tobe expressly understood, however, that the drawings are for illustrationpurposes only and are not to be construed as defining the limits of theinvention.

FIG. 1 is an end view, partly in section, diagrammatically illustratingthe present invention embodied in a steam surface condenser;

FIG. 2 is a diagrammatic sectional view taken generally on line 2-2 ofFIG. 1;

FIG. 3 is a view similar to FIG. 1 diagrammatically illustrating amodified embodiment of the invention and a modified control meansthereof; and

FIG. 4 is a diagrammatic sectional view of the heating chamber of FIG. 1and a further modified control means of the invention.

Although the present invention and the principles thereof are broadlyapplicable to liquid deaeration, in general, the present invention isparticularly adapted for use in conjunction with condensers, within orwithout a condenser shell, hence, it has been so illustrated and will beso described.

Referring now to the drawings and particularly to FIGS. 1 and 2, a steamsurface condenser 10 has an outer shell 12 and a standard tube bundle 14which carries cooling water for condensing steam delivered to thecondenser 10 at a steam inlet 16. Steam from inlet 16 flowslongitudinally through the condenser 10 across the tube bundle 14 duringwhich time it is condensed and the resulting condensate falls or dropsinto a reservoir or condenser hot well 18, while released noncondensableelements are discharged from condenser 10 by standard removal equipment40 (not shown), well known in the art, having a discharge or take-offline 42. However, as hereinbefore described, some of the noncondensableelements are reabsorbed by condensate in hot well 18.

To effect a substantially complete removal of noncondensables from thecondensate, a processing chamber 20 y is provided in or adjacent to hotwell 18 and, as shown in FIG. 2, is in communication with hot well 18through a water seal 22 formed by a wall open at the bottom between hotwell 18 and chamber 20 to receive condensate therefrom. A pump 26 isconnected to chamber 20 by condensate outlet or discharge line 24 topositively remove condensate from condenser 10. Condensate, therefore,flows from hot well 18 through seal or opening 22 into processingchamber 20 from whence it is discharged through the condensate outlet24.

To further remove noncondensable elements while condensate is in thechamber 20, a medium, such as heating steam, is provided from anexternal source (not shown) by a line 28. The heating steam is injectedor discharged from inlet line 28 directly into the condensate bysuitable means, such as a spray, a perforated header, or a pipe coil andheats the condensate to its boiling temperature at the pressure existingin chamber 20' for releasing substantially all of the remainingnoncondensable elements.

A conduit or duct 30 in communication with chamber 20 is provided topass noncondensable elements released from condensate in chamber 20,such as air, together with attendant steam, into the steam flow frominlet 16, immediately above the tube bundle 14, and subject thenoncondensable elements to the full influence of the removal equipment40 which are effectively removed from the condenser through line 42.

T o automatically control injection of heating steam into chamber 20,control means for maximum efficiency may be provided but, is notessential to the practices of the present invention. One form ofimplementation of such control means is shown in FIGS. 1 and 2 whereinan orifice plate 32 is provided in duct 30 and a control assembly 34 hasa flow control valve 38 connected in line 28 to control flow of heatingsteam to chamber 20. The control assembly 34 may be of a well-knowntype, having a pressure responsive element, for example, a diaphragmresponsive to pressure drop across orifice 32 or to the pressure inchamber 20 for controlling by electrical, pneumatic or any other wellknown means, the automatic steam flow control valve 38 for controllingflow of heating steam to chamber 20. The automatic control assembly 34has sensors on both sides of orifice 32 or in chamber 20 to sensepressure differential or pressure to which it responds with its valve 38for controlling flow in line 28 to provide a desired quantity of heatingsteam, irrespective of condensate flow or temperature, to cause boilingof condensate in chamber 20 at a pressure slightly higher than thepressure present in steam inlet 16. Thus, condensate in chamber 20 ismaintained at boiling temperature to release the noncondensa-bleelements, and sufficient pressure drop across orifice 32 or pressure inchamber 20 is maintained to assure positive flow of noncondensableelements and attendant steam into the steam flow from inlet '16.

It will now be understood that as the pressure drop across orifice 32 orthe pressure in chamber 20 varies, the control assembly 34 will respondto such change and automatically adjust its control valve 38 to delivermore or less heating steam, as required, to chamber 20. Therefore, theflow of heated steam to chamber 20 is controlled by pressure drop acrossorifice 32 or pressure in chamber 20 irrespective of the rate ofdischarge flow of condensate or chamber temperature. Therefore,condensate discharged through condensate outlet 24 is substantially freefrom noncoudensables.

Although chamber 20 and duct 30 heretofore have been described as beingenclosed within the shell of condenser 10, as shown in FIGS. 1 and 2, itshould be understood that there may be times, such as modifying anexisting condenser installation, when it is necessary or desirable toprovide the novel apparatus externally or as an attachment to acondenser. To accomplish this, as shown in FIG. 3, adjacent walls ofcondenser 10 and chamber 20 have aligned openings in their bottoms toprovide a Water seal 22A corresponding to seal 22 to provide a flow pathfor condensate from hot Well 18. Duct 30 now extends upwardly along thewall of condenser 10, extends therethrough immediately above tube bundle14, and terminates in the same location as in FIG. 1.

Alternatively, it will be understood that flow in line 28 of externalheating steam to chamber 20 can be controlled in response to changes inthe condensate level in chamber 20, or changes in the difference betweenthe levels of condensate in hot well 18 and chamber 20. Towards thisend, as also shown in FIG. 3, a liquid level or liquid leveldiiferential responsive control assembly 34A, corresponding to assembly34, automatically controls its valve 38A, corresponding to valve 38,connected in line 28. To provide the required signals, assembly 34A hasa liquid level sensor in chamber 20 when responsive to changes of thelevel of liquid therein and a second such liquid level sensor in hotwell 18 when responsive to changes in liquid level differential.

Further, alternatively, the flow of heating steam to chamber 20 can bedirectly controlled in response to the oxygen content of dischargedcondensate. As shown in FIG. 4, a control assembly or oxygen analyzer34B is provided in condensate discharge line 24 and automaticallyoperates its valve 38B, corresponding to valve 38.

It should be realized that practice of the present invention may beaccomplished by the apparatus of either FIG. 1 or FIG. 3 in the absenceof means for controlling the flow of heating steam or in conjunctionwith any of the control means shown in FIGS. 2 to 4. The rate of flow ofheating steam for the novel apparatus in the absence of control means isdetermined by normal or mean operating conditions. i

It noW will be understood by those skilled in the art that the objectsof the present invention have been achieved by providing means forfreeing noncondensable elements from condensate, in an atmospherenoncondncive to reabsorption, with positive venting of suchnoncondensables to removal equipment to insure condensate substantiallyfree from noncondensable elements.

Although several embodiments of the invention have been illustrated anddescribed in detail, it is to be expressly understood that the inventionis not limited thereto. Various changes may be made in the design andarrangement of the parts without departing from the spirit and scope ofthe invention as the same will now be understood by those skilled in theart.

I claim:

1. For use in combination with a condenser having a casing with inletmeans for steam, means disposed within said casing below said inlet forcondensing said steam and a reservoir for condensate, apparatus forremoving noncondensable material from the condensate comprising:

a chamber means for receiving condensate from said reservoir and forprocessing said condensate to free noncondensable elements therefrom andhaving an outlet for releasing condensate from the condenser;

rneans providing a passage between the reservoir and the chamber forallowing condensate in the reservoir to pass into the chamber andproviding a fluid seal between said reservoir and said chamber;

means operatively associated with the chamber for creating pressure inthe chamber in excess of the pressure in the steam inlet to therebymaintain the level of condensate in the chamber below the level ofcondensate in the reservoir and for freeing noncondensable elements fromcondensate in the chamber;

means for regulating said means for creating pressure in the chamber inexcess of the pressure in the steam inlet; and

duct means connecting the chamber to the condenser between the steaminlet and the condensing means for receiving noncondensable elementsfreed from the condensate in the chamber and releasing such elementsinto the condenser between said steam inlet and said condensing means.

2. Apparatus in accordance with claim 1, wherein:

the means for freeing noncondensable elements is an inlet line adaptedto receive a heating medium, and extending into the chamber andcondensate therein to discharge such heating medium into the condensatefor causing the condensate to boil and release noncondensable elementstherein.

3. Apparatus in accordance with claim 2, wherein:

the means for freeing noncondensable elements includes a restrictiveorifice operatively associated with the duct means causing pressure inthe chamber to rise when condensate is heated.

4. Apparatus in accordance with claim '3 wherein said means forregulating said means for creating pressure in the chamber in excess ofthe pressure in the steam inlet includes a valve connected in the inletline to control flow of the heating medium therethrough to the chamber;and

control means operatively connected to the valve for automaticallyadjusting the valve to control flow of the heating medium in accordancewith pressure in the chamber, and having a sensor disposed in thechamber for sensing such pressure.

5. Apparatus in accordance with claim 3 wherein said means forregulating said means for creating pressure in the chamber in excess ofthe pressure in the steam inlet includes a valve connected in the inletline to control flow of the heating medium therethrough to the chamber;and

control means operatively connected to the valve for automaticallyadjusting the valve to control flow of heating steam in accordance withthe pressure drop across the restricted orifice, and having a sensordisposed on each side of the restricted orifice for sensing pressurethereat.

6. Apparatus in accordance with claim 3 wherein said means forregulating said means for creating pressure in the chamber in excess ofthe pressure in the steam inlet includes a valve connected in the inletline to control flow of the heating medium therethrough to the chamber;and

control means operatively connected to the valve for automaticallyadjusting the valve to control flow of the heating medium in accordancewith the level of condensate in the chamber, and having :a sensor in thechamber for sensing the level of such condensate.

7. Apparatus in accordance with claim 3 wherein said means forregulating said means for creating pressure in the chamber in excess ofthe pressure in the steam inlet includes a valve connected in the inletline to control the flow of the heating medium therethrough to thechamber; and

control means operatively connected to the valve for automaticallyadjusting the valve to control flow of the heating medium in accordancewith the differ ence between the levels of condensate in the chamber andthe condenser, and having a pair of sensors for sensing liquid levels ofwhich one is disposed in the chamber and the other is adapted to bedisposed in the condensor.

8. Apparatus in accordance with claim 3 wherein said means forregulating said means for creating pressure in the chamber in excess ofthe pressure in the steam inlet includes a valve connected in the inletline to control the flow of the heating medium therethrough to thechamber; and

an analyzer connected to the outlet and the valve for analyzing thecontent of noncondensable elements in the condensate released from thechamber and automatically adjusting the valve to control the flow of theheating medium in accordance with the results of such analyzing.

9. In combination with a condenser having a casing with an inlet adaptedto receive steam to be condensed, a tube bundle in the casing with acooling medium passing therethrough for condensing steam, a reservoir insaid casing below said tube bundle for receiving condensate resultingfrom condensation, and equipment in said casing for removingnoncondensable elements from the condenser after being released from thesteam; apparatus for removing noncondensable elements from thecondensate, said apparatus comprising:

a chamber means disposed in the casing for processing condensate to freenoncondensable elements therefrom, and having an outlet for releasingcondensate from the condenser;

a wall disposed between the reservoir and the chamber having an openingtherethrough for allowing condensate in the reservoir to pass into thechamber, said opening positioned below the level of condensate 6 in saidreservoir to form a fluid seal between the reservoir and chamber;

means operatively associated with the chamber for freeing noncondensableelements from condensate in the chamber, and for creating pressure inthe chamber in excess of pressure in the steam inlet; and

duct means in the casing and in communication with the chamber forreceiving noncondensable elements freed from the condensate andreleasing such elements into the inlet flow of steam to be condensed.

10. The combination in accordance with claim 9,

wherein:

the means for freeing noncondensable elements is an inlet line adaptedto receive a heating medium, and extending into the chamber andcondensate therein to discharge such heating medium into the condensatefor causing the condensate to boil and release noncondensable elementstherein.

11. The combination in accordance with claim 10,

wherein:

the means for freeing noncondensable elements includes a restrictiveorifice operatively associated with the duct means causing pressure inthe chamber to rise when condensate is heated.

12. The combination in accordance 'with claim 11, and

further comprising:

a valve connected in the inlet line to control flow of the heatingmedium therethrough to the chamber; and

control means operatively connected to the valve for automaticallyadjusting the valve to control flow of the heating medium in accordancewith pressure in the chamber, and having a sensor disposed in thechamber for sensing such pressure.

13. The combination in accordance with claim 11, and

further comprising:

a valve connected in the inlet line to control flow of the heatingmedium therethrough to the chamber; and

control means operatively connected to the valve for automaticallyadjusting the valve to control flow of heating steam in accordance withthe pressure drop across the restricted orifice, and having a sensordisposed on each side of the restricted orifice for sensing pressurethereat.

14. The combination in accordance with claim 11, and

further comprising:

a valve connected in the inlet line to control flow of the heatingmedium therethrough to the chamber; and

control means operatively connected to the valve for automaticallyadjusting the valve to control flow of the heating medium in accordancewith the level of condensate in the chamber, and having a sensor in thechamber for sensing the level of such condensate.

15. The combination in accordance with claim 11, and

further comprising:

a valve connected in the inlet line to control the flow of the heatingmedium therethrough to the chamber; and

control means operatively connected to the valve for automaticallyadjusting the valve to control flow of the heating medium in accordancewith the difierence between the levels of condensate in the chamber andthe reservoir, and having a pair of sensors for sensing liquid levels ofwhich one is disposed in the chamber and the other is disposed in thereservoir.

16. The combination in accordance with claim 11, and

further comprising:

a valve connected in the inlet line to control the flow of the heatingmedium therethrough to the chamber; and

an analyzer connected to the outlet and the valve for analyzing thecontent of noncondensable elements in the condensate released from thecondenser and 7 automatically adjusting the valve to control the flow ofthe heating medium in accordance with the results of such analyzing.

References Cited UNITED STATES PATENTS 467,715 1/ 1892 Dugan 55-208 X1,180,786 4/ 1916 Munzinger 55-208 X 1,592,195 7/ 1926 Fothergill 55208X '8 3/ 1927 Jones 55-208 X 7/ 1929 Hodgkinson 165-412, 7/1929 Taddiken1, 5 -112 FOREIGN PATENTS 2/ 1929 Great Britain.

ROBERT A. OLEARY, Primw y Exmmin'er.

9. IN COMBINATION WITH A CONDENSER HAVING A CASING WITH AN INLET ADAPTEDTO RECEIVE STEAM TO BE CONDENSED, A TUBE BUNDLE IN THE CASING WITH ACOOLING MEDIUM PASSING THERETHROUGH FOR CONDENSING STEAM, A RESERVOIR INSAID CASING BELOW SAID TUBE BUNDLE FOR RECEIVING CONDENSATE RESULTINGFROM CONDENSATION, AND EQUIPMENT IN SAID CASING FOR REMOVINGNONCONDENSABLE ELEMENTS FROM THE CONDENSER AFTER BEING RELEASED FROM THESTEAM; APPARATUS FOR REMOVING NONCONDENSABLE ELEMENTS FROM THECONDENSATE, SAID APPARATUS COMPRISING: A CHAMBER MEANS DISPOSED IN THECASING FOR PROCESSING CONDSENATE TO FREE NONCONDENSABLE ELEMENTSTHEREFROM, AND HAVING AN OUTLET FOR RELEASING CONDENSATE FROM THECONDENSER; A WALL DISPOSED BETWEEN THE RESERVOIR AND THE CHAMBER HAVINGAN OPENING THERETHROUGH FOR ALLOWING CONDENSATE IN THE RESERVOIR TO PASSINTO THE CHAMBER, SAID OPENING POSITIONED BELOW THE LEVEL OF CONDENSATEIN SAID RESERVOIR TO FORM A FLUID SEAL BETWEEN THE RESERVOIR ANDCHAMBER; MEANS OPERATIVELY ASSOCIATED WITH THE CHAMBER FOR FREEINGNONCONDENSABLE ELEMENTS FROM CONDENSATE IN THE CHAMBER, AND FOR CREATINGPRESSURE IN THE CHAMBER IN EXCESS OF PRESSURE IN THE STEAM INLET; ANDDUCT MEANS IN THE CASING AND IN COMMUNICATION WITH THE CHAMBER FORRECEIVING NONCONDENSABLE ELEMENTS FREED FROM THE CONDENSATE ANDRELEASING SUCH ELEMENTS INTO THE INLET FLOW OF STEAM TO BE CONDENSED.